Maine Looks To Legalize ‘Missing Middle Housing’

Maine could become the third state to eliminate single-family-only zoning to encourage light density increases in residential areas and make it easier for homeowners to build accessory dwelling units.

2 minute read

April 27, 2022, 5:00 AM PDT

By Diana Ionescu @aworkoffiction


The Maine state legislature is one step closer to passing a bill legalizing duplexes, accessory dwelling units, and other “missing middle housing” types in neighborhoods previously zoned for single-family homes. As Christian Britschgi writes, the state is following the example of California and Oregon, which have both eliminated single-family only zoning and, in the case of California, established housing production goals.

“The measure has attracted bipartisan support, reflecting a growing consensus that local governments' zoning regulations are making housing unaffordable and that state preemption of those regulations is one means of bringing housing costs down and returning rights to property owners,” Britschgi says.

Maine's legislation would require municipalities to allow two-unit homes everywhere that single-family homes are allowed today, and to allow four-unit homes in designated growth areas. The bill would also guarantee homeowners the right to build accessory dwelling units (ADUs)—sometimes known as granny flats or in-law suites—on their single-family properties.

The bill would allow localities to limit ADU size, but ban them from requiring additional on-site parking. “The bill also eases density restrictions and parking requirements for deed-restricted affordable housing in multifamily-zoned areas. Provided they offer units for rent or sale at specific below-market rates, these developments can be built at 2.5 times the density of whatever the multifamily zone already allows.”

Critics of the bill say taking control away from local leaders could lead to overdevelopment and strained infrastructure and local services. Some also point out the nebulous and shifting definition of “affirmatively furthering fair housing.”

Others question whether the legislation would have any impact at all—California’s early experience does not exactly inspire confidence, although the state is taking steps to make ADU construction cheaper and more feasible for more property owners. According to Britschgi, allowing localities to set rules for ADUs “opens the door to localities setting up lengthy, discretionary approval processes that discourage people from actually building them.”

Monday, April 25, 2022 in Reason

portrait of professional woman

I love the variety of courses, many practical, and all richly illustrated. They have inspired many ideas that I've applied in practice, and in my own teaching. Mary G., Urban Planner

I love the variety of courses, many practical, and all richly illustrated. They have inspired many ideas that I've applied in practice, and in my own teaching.

Mary G., Urban Planner

Get top-rated, practical training

Close-up of "Apartment for rent" sign in red text on black background in front of blurred building

Trump Administration Could Effectively End Housing Voucher Program

Federal officials are eyeing major cuts to the Section 8 program that helps millions of low-income households pay rent.

April 21, 2025 - Housing Wire

Logo for Planetizen Federal Action Tracker with black and white image of U.S. Capitol with water ripple overlay.

Planetizen Federal Action Tracker

A weekly monitor of how Trump’s orders and actions are impacting planners and planning in America.

April 30, 2025 - Diana Ionescu

Ken Jennings stands in front of Snohomish County Community Transit bus.

Ken Jennings Launches Transit Web Series

The Jeopardy champ wants you to ride public transit.

April 20, 2025 - Streetsblog USA

Close-up of white panel at top of school bus with "100% electric" black text.

Driving Equity and Clean Air: California Invests in Greener School Transportation

California has awarded $500 million to fund 1,000 zero-emission school buses and chargers for educational agencies as part of its effort to reduce pollution, improve student health, and accelerate the transition to clean transportation.

5 hours ago - California Air Resources Board

Aerial view of Freeway Park cap park over I-5 interstate freeway in Seattle, Washington at night.

Congress Moves to End Reconnecting Communities and Related Grants

The House Transportation and Infrastructure Committee moved to rescind funding for the Neighborhood Equity and Access program, which funds highway removals, freeway caps, transit projects, pedestrian infrastructure, and more.

6 hours ago - Streetsblog USA

"No Thru Traffic - Open Streets Restaurants" sign in New York City during Covid-19 pandemic.

From Throughway to Public Space: Taking Back the American Street

How the Covid-19 pandemic taught us new ways to reclaim city streets from cars.

7 hours ago - Next City